This invention relates to computers, and particularly to the accommodation of computers and microcomputers to accessory cards of varying types through the provision of modular backplane assemblies.
As used in this description, "microcomputer" means that type of small computer apparatus which has come into general use in businesses and homes and in which a main processor or central processing unit (CPU) is housed in a cabinet of a size suitable for placing on or beside a desk or workstation and for accommodating accessory cards such as monitor display drivers, magnetic memory disk drivers, serial or parallel or game ports, and the like. Persons knowledgeable about computers generally will be familiar with microcomputers and the IBM standard which has been widely adopted by makers of so-called "clones" of the IBM models known as the PC, XT and AT machines.
The recent development of technology for microcomputers, including developments by IBM, the originator of a standard which has been widely adopted, has been such that there are proposals for several differing systems of accessory card connection and mounting. Two examples are the prior IBM standard which has been widely adopted and the more recent IBM development known as microchannel architecture (MCA).
It has been the industry practice to provide a computer which is capable of accepting accessory cards designed and built to be accepted in one system and not in others. That is, a machine constructed to accommodate accessory cards constructed to the prior standard is incapable of accepting cards constructed to the MCA standard, and vice versa. Thus a user is faced with a basic choice in selecting a machine and any prior assortment of accessory cards must be discarded and replaced if a change is made from one system to the other.
Such choices are not limited to microcomputers. Similar architectural choices must be made for computers generally, as is known to persons skilled in the applicable arts.